| 1. |
- Aberg, I, et al.
(författare)
-
Nanoscale tungsten aerosol particles embedded in GaAs
- 2002
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 80:16, s. 2976-2978
-
Tidskriftsartikel (refereegranskat)abstract
- GaAs containing buried nanoscale tungsten particles has been characterized electrically. The particles were produced using a special aerosol process and were embedded in GaAs by epitaxial overgrowth. Two different particle sizes were investigated separately. When the particle concentration was increased, a conductance drop of about 500 times was observed. A simulation model, based on a random distribution of the particles, was developed and used to support our findings. The major advantage of our method is the simplicity and low processing cost.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Aromaa, Mikko, et al.
(författare)
-
Atmospheric synthesis of superhydrophobic TiO2 nanoparticle deposits in a single step using Liquid Flame Spray
- 2012
-
Ingår i: Journal of Aerosol Science. - : Elsevier BV. - 0021-8502. ; 52, s. 57-68
-
Tidskriftsartikel (refereegranskat)abstract
- Titanium dioxide nanoparticles are synthesised in aerosol phase using the Liquid Flame Spray method. The particles are deposited in-situ on paperboard, glass and metal surfaces. According to literature, titanium dioxide is supposed to be hydrophilic. However, hydrophobic behaviour is observed on paperboard substrates but not on metal or glass substrates. Here, the water contact angle behaviour of the deposits is studied along with XRD, XPS, BET and HR-TEM. The deposits are compared with silicon dioxide deposits having, as expected, hydrophilic properties synthesised with the same method. It seems probable that the deposition process combusts some substrate material from the paperboard substrate, which later on condenses on top of the deposit to form a carbonaceous layer causing the hydrophobic behaviour of the TiO2 deposit. The similar layer does not form when depositing the nanoparticles on a metal or glass surfaces. The observations are more than purely aerosol phenomena. However, they are quite essential in nanoparticle deposition from the aerosol phase onto a substrate which is commonly utilised. (C) 2012 Elsevier Ltd. All rights reserved.
|
|
| 5. |
- Balmes, Olivier, et al.
(författare)
-
Reversible formation of a PdCx phase in Pd nanoparticles upon CO and O-2 exposure
- 2012
-
Ingår i: Physical Chemistry Chemical Physics. - : Royal Society of Chemistry (RSC). - 1463-9084 .- 1463-9076. ; 14:14, s. 4796-4801
-
Tidskriftsartikel (refereegranskat)abstract
- The structure and chemical composition of Pd nanoparticles exposed to pure CO and mixtures of CO and O-2 at elevated temperatures have been studied in situ by a combination of X-ray Diffraction and X-ray Photoelectron Spectroscopy in pressures ranging from ultra high vacuum to 10 mbar and from room temperature to a few hundred degrees celsius. Our investigation shows that under CO exposure, above a certain temperature, carbon dissolves into the Pd particles forming a carbide phase. Upon exposure to CO and O-2 mixtures, the carbide phase forms and disappears reversibly, switching at the stoichiometric ratio for CO oxidation. This finding opens new scenarios for the understanding of catalytic oxidation of C-based molecules.
|
|
| 6. |
|
|
| 7. |
- Bayer, K., et al.
(författare)
-
Targeted deposition of Au aerosol nanoparticles on vertical nanowires for the creation of nanotrees
- 2007
-
Ingår i: Journal of Nanoparticle Research. - : Springer Science and Business Media LLC. - 1572-896X .- 1388-0764. ; 9:6, s. 1211-1216
-
Tidskriftsartikel (refereegranskat)abstract
- Complex tree-like nanostructures with controlled morphology are becoming increasingly important for the development of nanoscale devices. The position of branches on III-V semiconductor nanotrees is determined by the distribution of Au seed particles. Here we report the dependence of the distribution of Au aerosol nanoparticles on nanowires on parameters including distance between wires, particle size, wire length, wire diameter, III-V material and particle charge. It was observed that different wire lengths and separation distances as well as different particle polarities have a significant effect on the resulting particle distribution while different wire diameters, particle diameters, materials and deposition voltages do not.
|
|
| 8. |
|
|
| 9. |
- Björk, Mikael, et al.
(författare)
-
Nanowire resonant tunneling diodes
- 2002
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 81:23, s. 4458-4460
-
Tidskriftsartikel (refereegranskat)abstract
- Semiconductor heterostructures and their implementation into electronic and photonic devices have had tremendous impact on science and technology. In the development of quantum nanoelectronics, one-dimensional (1D) heterostructure devices are receiving a lot of interest. We report here functional 1D resonant tunneling diodes obtained via bottom-up assembly of designed segments of different semiconductor materials in III/V nanowires. The emitter, collector, and the central quantum dot are made from InAs and the barrier material from InP. Ideal resonant tunneling behavior, with peak-to-valley ratios of up to 50:1 and current densities of 1 nA/mum(2) was observed at low temperatures. (C) 2002 American Institute of Physics.
|
|
| 10. |
- Björk, Mikael, et al.
(författare)
-
One-dimensional heterostructures in semiconductor nanowhiskers
- 2002
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 80:6, s. 1058-1060
-
Tidskriftsartikel (refereegranskat)abstract
- We report on the growth of designed heterostructures placed within semiconductor nanowhiskers, exemplified by the InAs/InP material system. Based on transmission electron microscopy, we deduce the interfaces between InAs and InP to be atomically sharp. Electrical measurements of thermionic emission across an 80-nm-wide InP heterobarrier, positioned inside InAs whiskers 40 nm in diameter, yield a barrier height of 0.6 eV. On the basis of these results, we propose new branches of physics phenomena as well as new families of device structures that will now be possible to realize and explore.
|
|
